under each image it indicates which of the three periods it was made and Strathearn still has a question mark. That means that so far a labeled or sealed Strathearn example has not been seen. Yours looks like it could be Strathearn but later Vasart had some of the same colours. In the early days at Strathearn they made things in the same way as they had being doing in Perth but because of the seal they had a problem with vases cracking and perhaps they did not always use the seal at the beginning. To resolve this they thickened the outer casing and this thickening solved the problem as well as giving an instant ID of Strathearn, seal or not.

So on balance it would make a Strathearn attribution very unlikely. The only other difference that occurred on the move to Crieff was that they used Propane to power the furnaces instead of Town-gas. As yet no one has come up with a means of determining if this had any affect on appearance or feel. The paperweight folks get round this by using the term transitional as weights made either side of the move are identical but this cannot work with the glassware except as wishful thinking.